Most successful people do not set goals, they establish systems.

Example goal: Lose 10 pounds

Example system: Work out 4 days per week

Notice that the example system looks a lot like a goal? Systems generally have an implicit goal, otherwise why waste the time. The distinction between a goal and a system is a goal is just a result whereas a system contains a strategy for achieving a result.

People that strive for goals are in a perpetual state of failure. The entire time you're working towards losing those 10 pounds you're failing. You haven't achieved your goal. This is self limiting, and a drain on your psyche. Even if you hit your goal, what comes next? You establish a new goal of course, and resign yourself to more and more failure. If you work out 4 days a week you're winning. Even if you don't drop those 10 pounds you're still successful because you're following the system. And by simply working out 4 days a week you might exceed your expectations of losing 10 pounds. Goals limit the end result, systems allow for continuous success.

Example Goal: Get rich

Example System: Save 50% of income, and invest in low fee index funds

Which person do you think will be successful more here? Both people have the implicit goal of acquiring money, but the system incorporates a strategy for achieving the underlying goal. The person with the goal here could try any number of methods for achieving that goal, including self defeating behavior - gambling, lottery, illegal methods. The system is allowing the person to live on less then they earn, while concurrently investing huge sums of cash. They are also preparing themselves for the bumps along the way, such as declining income or an emergency.

Goals are short term. Systems last forever.

Or until you die.

Credit for the idea:
How to Fail at Almost Everything and Still Win Big: Kind of the Story of My Life - Scott Adams